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Resource Autoloaders

Resource autoloaders are intended to manage namespaced library code that
follow Zend Framework coding standard guidelines, but which do not have
a 1:1 mapping between the class name and the directory structure. Their
primary purpose is to facilitate autoloading application resource code,
such as application-specific models, forms, and ACLs.

Resource autoloaders register with the autoloader on instantiation,
with the namespace to which they are associated. This allows you to
easily namespace code in specific directories, and still reap the
benefits of autoloading.

Resource autoloader usage

Let's consider the following directory structure:

path/to/some/directory/

acls/

Site.php

forms/

Login.php

models/

User.php

Within this directory, all code is prefixed with the namespace
"My_". Within the "acls" subdirectory, the component prefix "Acl_"
is added, giving a final class name of "My_Acl_Site". Similarly, the
"forms" subdirectory maps to "Form_", giving "My_Form_Login". The
"models" subdirectory maps to "Model_", giving "My_Model_User".

You can use a resource autoloader to autoload these classes. To
instantiate the resource autoloader, you are required to pass at the
minimum the base path and namespace for the resources it will be
responsible for:

Note: Base namespace
In Zend_Loader_Autoloader, you are expected to
provide the trailing underscore ("_") in your namespace if your
autoloader will use it to match the namespace.
Zend_Loader_Autoloader_Resource makes the
assumption that all code you are autoloading will use an
underscore separator between namespaces, components, and
classes. As a result, you do not need to use the trailing
underscore when registering a resource autoloader.

Now that we have setup the base resource autoloader, we can add some
components to it to autoload. This is done using the
addResourceType() method, which accepts three
arguments: a resource "type", used internally as a reference name;
the subdirectory path underneath the base path in which these
resources live; and the component namespace to append to the base
namespace. As an example, let's add each of our resource types.

$resourceLoader->addResourceType('acl', 'acls/', 'Acl')

->addResourceType('form', 'forms/', 'Form')

->addResourceType('model', 'models/', 'Model');

Alternately, you could pass these as an array to
addResourceTypes(); the following is equivalent to the
above:

The Module Resource Autoloader

Zend Framework ships with a concrete implementation of
Zend_Loader_Autoloader_Resource that contains resource
type mappings that cover the default recommended directory structure
for Zend Framework MVC applications. This loader,
Zend_Application_Module_Autoloader, comes with the
following mappings:

forms/ => Form

models/ => Model

DbTable/ => Model_DbTable

mappers/ => Model_Mapper

plugins/ => Plugin

services/ => Service

views/

helpers => View_Helper

filters => View_Filter

As an example, if you have a module with the prefix of "Blog_", and
attempted to instantiate the class "Blog_Form_Entry", it would look
in the resource directory's "forms/" subdirectory for a file named
"Entry.php".

When using module bootstraps with Zend_Application, an
instance of Zend_Application_Module_Autoloader will be
created by default for each discrete module, allowing you to
autoload module resources.